Deregulation of the telecommunications industry has led to private ownership of telephone paystation and switching system technology resulting in competition to capture revenue among contending providers of both local and long distance call services. Both coin collection and credit billing from users of paystations are important sources of such revenue. The ability of a paystation owner to capture this revenue has been facilitated with the development of intelligent or so-called "smart" paystations capable of operating on a conventional telephone business line. Such paystations typically include their own microprocessor and associated memory for supporting various computer programs to perform functions which otherwise would be performed in a central office. The computer programs are able to provide enhanced services to both the user and call service provider which enable cost reduction and increased profitability at the paystation. Examples of enhanced services generally include automated operator services and other services such as automatic message delivery. Also, associated memory of the intelligent paystation can be used to store rate information for various long distance carriers.
Although intelligent paystations are advantageous, the use of other specialized telecommunication services and equipment is still required in the provision of local and long distance telephone call services from a paystation. Typically, a multiple paystation installation is connected via class-marked trunks, leased lines or standard business lines to a local telephone operating company central office. Each local telephone operating company operates within a so-called local access and transport area (LATA). Local calls are directed by the central office to the destination within the LATA. Long distance calls are carried between distant local telephone operating companies through the AT&T network or through one or more independent interexchange carriers (IXCs). When a long distance call is dialed, the call is usually transmitted through an operating company central office to a point of presence (POP) in the originating LATA at which it is picked up by the interexchange carrier and passed by that carrier on to a point of presence in a distant LATA. Upon reaching the destination LATA, the call is then transferred by the interexchange carrier to the local telephone operating company central office within that LATA for ultimate connection to the called station therein. Typically, the points of presence in each LATA include suitable switching circuits, e.g., an access tandem, that are interconnected by a digital serial link. Such a digital serial link is used to interconnect most central offices as well as to interconnect operating company switching networks to other types of switches, such as the cell site control switches of a mobile telephone network.
Accordingly, local telephone operating companies and other service providers typically participate in revenue generated from private paystations for their services and equipment utilized to complete a call. This participation is significant for those services which the paystation owner is unable to offer as well as for those services the owner does not choose to offer. For example, calls paid for by coin in advance of transmission from a paystation, referred to as coin calls or "sent paid" traffic, require intelligent coin signaling and accounting which can be handled either at an intelligent paystation or otherwise at a central office for a fee. A limitation of intelligent paystations is their inability to interface directly with the rate table data base of individual interexchange carriers to facilitate the delivery of sent paid calls through the individual carriers. Rate information updates therefore require changes to data stored in each paystation location. A limitation of local telephone operating company central offices is that they typically do not offer interexchange carriers equal access to sent paid traffic from paystation installations.
Also, automated operator services are provided both from intelligent paystations and from central office locations. Automated operator services enable collection of revenue from a paystation for completion of a collect call, a call billed to a credit card or account number, or a call placed using a variety of other billing access formats. Further, other enhanced services such as automatic message delivery are capable of being performed either from a central office or an intelligent paystation.
However, there are limitations associated with providing the foregoing services at either the paystation or the central office. A limitation of providing enhanced services from a central office is that new services are not easily incorporated into the switch circuitry of the central office. The central office switch circuitry typically controls up to ten thousand lines and outbound links to multiple local central offices. Further, to interface the incoming lines to outgoing interexchange carriers, instructions such as Feature Group D routing information must be immediately accessed by the switch circuitry. Programming for controlling the switch functions is extremely complex and is not easily modified. Disfunctioning program modifications create a potential for rendering the switch circuitry inoperable.
A limitation of providing the foregoing services from a multiple paystation installation is the hardware cost associated with building each intelligent paystation or refurbishing existing standard ("dumb") paystations to incorporate the necessary intelligence. Further, multiple intelligent paystations are not readily modified to incorporate new services nor are they easily controlled to select the particular services for deployment in individual paystations. Intelligent paystations are also limited in that they typically do not offer caller access to other enhanced service providers.